Pretty much every evo person uses the Hobbs switch for the second pump. You could also control it thru the ecu. (Maybe?) it would be set up like a nitrous WOT switch
A single 450 is supposed to support ~800hp I think on pump gas. As long as it’s rewired to battery with a relay
I have dual in tank walbro 155’s feeding a return style fuel system and it heated up my fuel too much with them both on constantly. I’m not a boosted set up, just bigger cube NA with nitrous so I wired up my second pump to the nitrous toggle. Essentially I run one pump NA and the second get triggered for nitrous.
You can also hook it up to a RPM switch just like for nitrous so the second pump gets triggered at say 3500 rpm or whatever you want.
I like the hobbs swet to 2or3 psi. It works with every setup I seen and wonder what happened with Drews.
You will need to set it at a low boost level because of the short time it takes to build boost once your already climbing and give the pump time to produce some fuel flow.
Bump.
Some work got done. I got the engine in myself, really went much smoother than I thought.
Spent most of Saturday trying to figure out why the car would only start intermittently and wouldn’t stay running for more than 2 seconds. I played around with the tune, used different base tunes, etc. I then noticed a ground wire on the passenger side in the headlight harness was off. Hooked up that ground, and fired right up.
(sorry, my phone camera lens is packed with shit).
Does anyone have a valve cover bolt? I somehow managed to lose one in the rebuild process. The ones I need have black gaskets / grommets, I have a few I found laying around with gray gaskets, but they are too long to seal into the cover.
I need to get the charge piping back in, get vacuum lines ran to the bov, waste gate, and boost gauge, bleed the brakes, do some massive wire orgainization under the hood, tap a new turbo oil supply (mine is leaking bad, somehow got cracked in the process). I hope to have moving under it’s own power by next weekend.
Also looking for a drag wheel setup if anyone knows of anything.
You get your fuel stuff figured out? I’m running a 044 Bosch pump kicked on with a couple PSI on my vette
I think mine was just a faulty switch. I have used them before and it worked well. I just have been too lazy to look into it.
I have twin in-tank walbro 255’s. A 8 gauge feed split into 2 separate relays. The first relay is triggered by the stock fuel pump wiring, the second relay is triggered by the hobbs switch (just ordered today, not installed yet). I’m going to use the stock feed and returnless system for now. If I have issues with boiling fuel or tuning in boost I’ll just get a regulator and run a new feed an use the stock feed as a return.
I don’t want to get too far into the fueling, if things go well this year I want to really step it up for next year and I’ll probably end up redoing it all again.
I’m hoping to start street tuning this weekend.
I’ve tried researching a reason why people prefer to tune as close to a 1-1 ratio as they can, in my case 3rd gear, and haven’t come up with much. What is the reason for this? I’m currently still running 2.73’s so tuning to the top of 3rd’s rpm range on local streets is a bit difficult. What is the disadvantage to using 2nd gear as the basis for the tune?
@cougarspeed, @lz
Because there is more load on the engine at 1:1 if you tuned it at WOT in 2nd the AFR won’t be correct in 3rd.
Doing part throttle, idle, cruising on the street is pretty easy those 2.73s go forever I had them on my old Formula.
You know they have this thing called a dyno you can tune it on 
I tune every gear. If you get it pretty good in 2nd you would only need 1-2 3rd rips to get it all square.
Fucking thing started saturday, no problem. Tried to start it Sunday and nothing again…ugh, lostttttttt
Updates?
It runs and drives, but is currently untuned. With weather cooperating, I still might get a tune on it this year - issue being that the car is not currently on the road, and probably won’t be registered until next spring.
I need to get a windshield, and alignment, and I think one of my Viking coilovers is shot (with <2000 miles on it)…so couple things to wrap up before it is really road worthy. I also had a bit of a ‘mishap’ and need a new driver fender and mirror.
I should be out running 11’s next year…Either that, or selling both this and the c5 to get myself a C6.
C6 ftw
Well, I just drove the car about 10 miles and ran into oil pressure issues.
Oil psi was great when I started. After a few minutes I did a couple quick pulls, after the third pull, I noticed that the oil PSI was well under 20psi at 2500ish rpm, and it would not increase with rpm changes, so I pulled the car over and shut it down.
After waiting a couple minutes, I started the car back up, and oil psi shot back up to 30ish. I started driving again, everything seemed normal for about 2 minutes, and then the pressure started to go back towards 0. So I pulled over, shut it down again for a few minutes, then started it back up and hit 30ish again.
I drove home, pulling over 2 more times when the psi got low, and after restarting each time it came back up to decent pressure for a bit.
Sooooo, I think this afternoon I’ll pull the pan and check the pickup for debris, and replace the aftermarket (used melling) oil pump with the 5.3 stocker and see if anything changes. I doubt it’s the pickup o-ring because I would think I would have low pressure at all times, not just after a few minutes of driving.
partial throttle playing around at the boost threshold. Forgot what boost was like… Too bad I have to tear it apart again. I think I’m going to just pull the engine out again.
Nice, blows you gotta pull it out.